Enlarge the bounding sphere with the primitive's bounds. By default, this will enlarge the bounding sphere by the primitive's bounding box (i.e. getBBox()). It may be possible to have a tighter bound (i.e. the vertex hull for many primitives is a much better metric).

Private interface The clearForDeletion() method is called just prior to the detail being cleared out. This allows the primitive to simplify its data structures, knowing that topology doesn't need to be maintained (i.e. unwiring all vertices);